11% of COVID-19 survivors have residual lung damage, study finds

News brief

A new study in the American Journal of Respiratory and Critical Care Medicine reveals about an 11% incidence of residual lung damage—known as interstitial lung disease—after COVID-19 hospitalization. Interstitial lung disease is a broad category of lung damage and disease defined by fibrotic scarring. The damage is often irreversible.

"For some people these fibrotic patterns may be stable or resolve, while for others they may lead to longer term lung fibrosis progression, worse quality of life and decreased life expectancy. Earlier detection of progression is essential to improving outcomes," said study lead author Iain Stewart, PhD, of Imperial College London in a press release.

The study was based on the UK Interstitial Lung Disease (UKILD) study, which enrolled participants who were discharged from the hospital by March 2021 and followed through October 2021.

The lung characteristics of 209 study participants who had CT scans were compared to a wider post-hospitalization cohort of almost 3,500 people without a CT to stratify risk of residual lung abnormalities.   

Of the 209 with CT scans, 164 people (79.6%) had greater than 10% involvement of residual lung abnormalities, with risk factors of an abnormal chest x-ray (risk ratio [RR], 1.21; 95% confidence interval (CI), 1.05 to 1.40) and severe illness requiring ventilation support (RR, 1.27; 95% CI, 1.07 to 1.55).

"These findings highlight the importance of radiological and physiological monitoring of patients at both early and later follow-up, and suggest up to 11% of people discharged from an acute COVID-19 admission are at risk of residual lung abnormalities," the authors concluded.

Three countries report more polio cases

News brief

The Democratic Republic of the Congo (DRC), Indonesia, and Yemen reported polio cases, all involving vaccine-derived types, according to the latest weekly update from the Global Polio Eradication Initiative (GPEI).

In the DRC, one more case involving circulating vaccine-derived poliovirus type 1 (cDVPV1) was reported, affecting a patient from Haut Lomami province, lifting the total for the year to 48. The country has also reported 191 cVDPV2 cases this year.

Indonesia's cVDPV2 case, its first, was first reported by the health ministry in November. GPEI said the virus was also isolated from three of the patient's healthy community contacts. A catch-up immunization campaign in the affected area launched on Nov 28 targeting 1.2 million children. Two more vaccination campaigns planned for January and February in four provinces will target 3.7 million children.

Elsewhere, Yemen reported four cVDPV2 cases from three different provinces, bringing its total for the year to 158.

Avian flu strikes more poultry farms in 4 states

News brief

More highly pathogenic avian flu outbreaks in poultry have been reported in four states, all involving commercial farms, according to the latest updates from the US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS).

In Missouri, the virus struck a turkey farm in Webster County that houses 15,100 birds, and in South Dakota, four more outbreaks were reported at turkey farms in Charles Mix, Hamlin, Hanson, and Spink counties, leading to a loss of about 230,000 birds.

Elsewhere, Illinois reported an outbreak at a game bird producer in Grundy County that has 8,000 birds, and Maryland reported an event at a layer bird breeding farm in Washington County, which houses 24,600 birds.

The US outbreaks in poultry involving the Eurasian H5N1 strain began in February and so far have led to the loss of a record 52.7 million birds across 46 states.

In other related developments, APHIS reported 20 more H5N1 detections in mammals, raising the total to 98. Many involved skunks, but the detections included other species, including a black bear from Alaska, red foxes from New York, a possum from Virginia, an Amur leopard in New York, a bottlenose dolphin in Florida, and a harbor seal in Maine.

In international developments, Hungary this week reported an H5N1 outbreak in poultry, its first since June, according to a notification from the World Organization for Animal Health (WOAH). The virus hit a farm in Bekes County in the southwestern part of the country that houses 3,080 birds.

Almost half of COVID patients globally had symptoms at 4 months

News brief

A meta-analysis led by University of Leicester researchers in the United Kingdom shows that nearly half of COVID-19 survivors around the world still had symptoms an average of 4 months later, regardless of whether they had been hospitalized.

The research, published yesterday in eClinicalMedicine, involved 194 studies of 735,006 participants with lingering COVID-19 symptoms at least 28 days after infection in Europe (106 studies), Asia (49), North America (26), South America (5), Africa (4), and Oceania (2) or multiple continents (2) from Dec 31, 2019, to Jan 21, 2022.

Of the 194 studies, each of which involved at least 100 participants, 5 were conducted in children aged 17 or younger and reported data on hospitalized (122 studies), nonhospitalized (18), or a combination of hospitalized and nonhospitalized (54) patients. Follow-up was 28 to 387 days.

At least 45% of COVID-19 survivors, on average, had at least one unresolved symptom at an average of 126 days. Fatigue was widely reported by hospitalized (28.4%), nonhospitalized (34.8%), and mixed (25.2%) cohorts. Other common symptoms were pain/discomfort (27.9%), impaired sleep (23.5%), breathlessness (22.6%), and impaired ability to participate in usual activities (22.3%).

Among hospital patients, abnormal computed tomography (CT) patterns/radiographs were often reported (45.3%), as were ground-glass opacities (hazy patches; 41.1%) and decreased capacity to diffuse carbon monoxide (31.7%).

"Current understanding is limited by heterogeneous study design, follow-up durations, and measurement methods," the study authors wrote. "Definition of subtypes of long Covid is unclear, subsequently hampering effective treatment/management strategies."

The researchers called for harmonization of data-collection tools to improve the clinical utility of findings from long-COVID systematic reviews, as well as more attention to the care of long-COVID patients.

"It is clear that given the high prevalence of persistent symptoms after 12 weeks (nearly 1 in 2 people) that healthcare services and policy need to prioritise long Covid care, and in addition understand different sub-types of long Covid to permit stratified healthcare and ensure services are not overwhelmed in future," they wrote.

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